This invention relates to an electric motor driven supercharger for use with an air cycle air conditioning system.
Aircraft air conditioning systems typically use compressed air supplied to an air conditioning pack from bleed air from a turbine engine. The bleed air is provided by bleed ports on the turbine engine and typically must be passed through a precooler prior to the air conditioning pack.
Pressurized air is provided by two bleed ports on the turbine engine. The selection of the bleed stage used during mid to high engine power settings are matched to the pressure required by the air conditioning system for high altitude, hot day cruise conditions or set by the location of the first engine compressor stage where it is convenient to extract the air from the engine compressors. In either case, once the bleed port is defined and the air conditioning system is designed to that pressure, at lower altitude flight conditions and/or cooler ambient day conditions there is more pressure than required by the air conditioning system. The excess bleed air pressure is throttled off as waste for all but the worst case conditions, such as the highest altitude at the hottest day.
Superchargers have been used to supply pressurized air to vapor cycle air conditioning packs. The superchargers are driven by turbines that are powered by bleed air. The supercharger arrangements have similar issues as systems providing pressurized air through bleed ports in that bleed air pressure driving the power turbine throttled off as waste.
What is needed is an aircraft air conditioning system that supplies only the needed pressure level of supplied air to the air conditioning pack to reduce waste of energy in the system.